Aerial refueling is a process of transferring fuel from a tanker aircraft to a receiving aircraft during flight. Aerial refueling allows a receiving aircraft to remain airborne longer and extend its range. Referring to FIG. 1, autonomous Aerial Refueling (AAR) 100 is a process whereby Unmanned Aerial Vehicles (UAV) 102 receive fuel from a tanker aircraft 101 during unmanned flight. AAR 100 allows an UAV 102 to remain airborne longer and extend its range. AAR 100 requires precise position determination for the tanker aircraft 101 and UAV 102 in order for the UAV 102 to travel to contact with the tanker aircraft 101 and receive fuel.
Typically, position determination for AAR 100 is provided by GPS (global positioning system). However, GPS may not be available for position determination (such as when GPS is jammed or is blocked). INS (inertial navigation system) could be utilized to determine position in a GPS-denied scenario, but excessive position error accumulation after several minutes of operation without GPS updates makes INS insufficient as a sole method of determining position for AAR 100.
Consequently, it would be desirable to provide autonomous GPS denied relative navigation which addresses the above-referenced problems and limitations of the current solutions.